A new roundabout at Oregon Highway 126 and Tom McCall Road in Prineville is expected to open Thursday morning after being closed for construction since January.

The roundabout will open at about 9 a.m., following the early morning commute period, Oregon Department of Transportation spokesman Peter Murphy said in an email. Finishing work will continue, but it will be open to traffic.

The $4 million project has been in the works since 2013, and traffic managers and engineers from ODOT and the city of Prineville tested it with a “roundabout rodeo” — a roundabout-shaped obstacle course for large trucks — at the Deschutes County fair in 2016.

Murphy advised drivers to slow down and pay close attention because travel patterns in the area will change. Workers plan to add more signs indicating travel paths.